//2009/08/20 23:37:38
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <queue>
#include <sstream>
#include <algorithm>

using namespace std;

class SkewSymmetric
{
public:
    int minChanges(vector <string> N)
    {
		vector<vector<int> > M;
		for(int i=0; i<N.size(); i++)
		{
			stringstream s(N[i]);
			vector<int> temp;
			int str;
			while(s >> str)
				temp.push_back(str);
			M.push_back(temp);
		}
		int ret = 0;
		for(int i=0; i<M.size(); i++)
		{
			for(int j=i; j<M[i].size(); j++)
			{
				if(M[i][j] + M[j][i] != 0)
					ret ++;
			}
		}
		return ret;
    }
};
